Apparatus for bending sheet metal



Aug., 9, 1932.

A. N. MERRYMAN 1,879,250

AFPARATUS FOR BENDNG SHEET METAL Filed Nov. 14, 1929 2 Sheets-Sheet lAug. 9, 1932. A. N. MERRYMAN APPARATUS FOR BENDING SHEET METAL 2Sheets-Sheet 2 Filed Nov. 14, 1929 Patented ug. 9, 1932 UNITED STATESPATENT OFFICEA SETTS ARTHUR N. MERRYMAN, OF WOBURN', MASSACHUSETTS,ASSIGNOR TO THE CHENEY COMPANY, OF -WINCHESTER, MASSACHUSETTS, ACORPORATION OF MASSACHU APPARATUS ron BENDING SHEETMETAL Application ledNovember 14, 1929. Serial No. 407,107.

This invention relates to an apparatus for bending sheet metal, andparticularly to an apparatus for forming dove-tail shaped grooves andridges upon said metal.

The object of the invention is to provide an apparatus of simpleconstruction which may be employed for the purpose of forming dove-tailshaped grooves and ridges, or grooves and ridges' having' under-cut sideportions and approximating a dove-tail shaped form upon strips of sheetmetal without stretching or otherwise weakening the metal during thebending operation.

Another object of the invention is to pro- Vide a means for positioningthe sheet material in order that aside portion of certain of thedove-tail shaped grooves may be formed at an angle to the oppositeside'portion of said groove.

The invention consists of an apparatus for bending sheet material as setforth in the following specification and particularly as pointed out inthe claims thereof.

Referring' to the drawings:

Figure 1 `represents a vertical section through the cooperating diemembers of an apparatus embodying` my invention, together with theadjacent portions of a. press upon which the die members are mounted andby means of which they are actuated, the die members being illustratedin their open positions.

F ig. 2 is a plan view of the lower die member and positioning means forthe sheet material, together with portions of the press upon which saiddie member is mounted, the intermediate portion of the die member beingbroken away to save space in the drawings.

F ig. 3 is a vertical section similar to Fig. l but illustrating the diemembers in their closed positions. Y

F ig. l is a perspective view of a strip of sheet material after it hasbeen operated upon by the apparatus of this invention to produce thedove-tail shaped grooves and ridges thereon. l

Like numerals refer to like parts throughoutthe several views of thedrawings.

In the drawings, 5 represents the side frames of a press of well knownform, 6 is the bed of said press and 7 is the press slide which ismounted in vertical guideways 8 formed in the side frames 5 and isadapted to have a vertical reciprocatory motion imparted thereto in awell known manner. Rigidly secured to the inner face of each side frame5 is an angle bar 9 which, in effect, forms a part of said side frame,and said bars constitute shelves to support end bearings 10 for a lowerdie member 11, the latter having a trunnion portion l2 formed at eachend thereof by means of which it is pivotally mounted in the bearings10.

The die member 11 embodies therein a detachable die plate 13. Projectinglaterally from the die member 11 adjacent to one end thereof is an arm14, and the die member 11 is normally held in a raised position, atwhich time the arm 14 engages a stop 15, by means of a spring 16, oneend of which is connected to the outer portion of the arm 14, and theother end of said spring being secured in any suitable manner (notshown) to a side frame 5.

Detachably secured to the under side of the slide 7 is an upper diemember 17 which embodies therein a die plate 18. The working faces ofthe die plates 13 and 18 are formed to co-operate with each other toform an under-cut bent portion a constituting a side portion of adove-tail shaped groove upon a strip of sheet material A, see Fig. 4.

Detaohably fastened to the bed 6 of the press is a support 19 whichconstitutes a stop to limit the downward movement of the lower diemember 11. Secured to the front surface of the die member 11 adjacent toone end thereof is an angular member 20 constituting an abutment, andsecured to the front face of the slide 7 directly above said abutment 2Ois an actuating member 21 which is adapted to engage the abutment duringthe downward movement of the slide 7 and impart a rocking movement tothe lower die member 11. The member 21 is so positioned upon the slide 7that during the downward movement of said slide the lower extremity ofsaid member will engage the upper surface of the abutment 20 at the sametime that the lower surface of the die plate 18 engages the uppersurface of the sheet material A, so Ythat during the rocking movement ofthe lower die member 11, the pressure that is eXerted by the slide 7 torock the die member 11 will be transmitted from said slide to the diemember through the actuated member 21 and abutment 20 and there will beno tendency for the die plate 18 to wrinkle or otherwise misform thesheet material during the downward and lateral movement of the dieVmember 11.

rlwo separate and distinct positioning means are provided for thepurpose of positioning the sheet metal A in order that the bent portionsa maybe correctly positioned thereon as follows 1-Secured to the frontface of the lower die member 11 upon one side portion thereof are anglebars 22 constituting supports for a positioning bar 23, the latter beingadjustably secured to the supports 22 by bolts 24 which extend throughthe bar 23 and through slots 25 provided in the supports 22. The bar 23extends parallel to the front edge of the die member 11 and is spacedapart from said front edge in accordance with the spacing that isdesired between the bent portions a of the sheet material.

Also secured to the front face of the lower die member 11 upon the otherside portion thereof is a support 26 for a positioning bar 27 whichis'pivotally attached at 28 to the support 26. Stop pins 29 projectupwardly yfrom the support 26 at opposite sides thereof in a manner tolimitv the rocking movement that can be imparted to the positioning bar27, one extreme position of which is illustrated in full lines, and theother extreme position being illustrated in dotted lines in Fig.Y 2.

Whenever it is desired to form a bend across the strip of sheet materialA at a predeter mined angle to a side edge of said sheet may terial,either the front edge of the material or a previously formed bentportion is moved into engagement with the edge of the bai-V27 and thelatter is rocked until it is moved into engagement with the desired stoppin 29, at which time the sheet material will be properly positioned tohave a bent portion formed thereon at the angle desired.

The general operation of the 'apparatus hereinbefore specicallydescribed is as fol'- lows z-The apparatus is preferably attended by twooperatives, one of whom stands Iat the front and side of eachpositioning means for a strip of sheet material and pulls the 'latterbetween the die members to receive the successive bending operations,positioning theA strip of 'sheet material prior to each bendingoperation. The operative who is stationed to the front and left handside of Fig. 2 grasps the sheet material at its opposite longitudinaledges andV pulls the same across the upper surface of the die member 11until the front edge of the Lsheet material abuts `against the rear edgeof the positioning member 23, after which the press is started inoperation in a well known manner to operate the press slide 7.

r1`he slide 7 descends until the lower surface of the die plate 18contacts lightly with the upper surface of the sheet material A, atwhich time the lower extremity of the actuating member 21 abuts againstthe upper surface of the abutment 20, and a continued downward movementof the slide 7 will cause the pivoted die membery 11 to be rockeddownwardly against the tension of the spring 16 until the lower side ofsaid die member contacts with the upper surface of the support 19, atwhich time the die plates 13 and 18 will have engaged the sheet materialA in a manner to fbrm an undercut bentk portion a upon the sheetmaterial A, as illustrated in Fig. 3.

As the die members again open, the strip of sheet material A is pulledforwardly beneath the positioning member 23 until the previously formedbent portion a is brought into Contact with the rear edge yofthepositioning member 23 and the press is again operated to form anotherbent portion upon the sheet material. After the entire ystrip ofmaterial A has been passed between the die members, the strip isreversed and passed to the attendant at the other side of the press andhe, in turn, positions the strip of material by abutting previouslyformed bent portions successively against the rear edge of thepositioning member 27 at the same time rocking said positioning memberuntil the latter contacts with one or another of the pins 29, at whichtime the sheet material will be positioned. to have a bent portionformed thereon oppositely to the previously formed bent portion, butalso at a slight angle thereto and to the longitudinal edges of thesheet material. Two attendants for the machine work simultaneously andtwo strips of sheet material are, therefore, operated uponsimultaneously to receive the bent portions. The finished product willhave alternately arranged grooves and ridges formed thereon asillustrated in Fig. 4.

I claim:

1. An apparatus of the character described having, in combination, aframe, a

vdie member pivotally mounted upon said frame, another die memberslidably mounted upon the frame, means to move the slidable die memberinto engagement with sheet material resting upon the pivoted die memberand thereafter impart a downward and lateral rocking movement to thelatter through pressure exerted against the sheet material by theslidable die member, whereby said die 'members will co-operate with eachother to bend the sheet material to'form an under-,cut portion thereon,and a positioning member adapted to be engaged by successive bentportions of the sheet material and thereby position the latter toreceive successive bending operations.

2. An apparatus of the character described having, in combination, aframe, a die member yieldably mounted upon said frame, another diemember slidably mounted upon the frame, means to move the slidable diemember into engagement with a sheet of material resting upon theyielding die member and thereafter impart a downward and lateralmovement to the latter, whereby said die members will co-operate witheach other to bend the sheet material to form an undercut portionthereon, positioning means for the sheet material, and means to vary theposition of said last-named means whereby the angle of the bent portionacross the sheet may be varied with relation to the oppositelongitudinal edges thereof.

3. An apparatus of the character described having, in combination, aframe, a die member pivotally mounted upon said trame, an arm projectinglaterally from said die member, a spring attached to said arm, anabutment projecting laterally from said diev member, another die memberslidably mounted upon the fram-e, an actuator fasl tened thereto, andmeans to move the slidable die member into engagement with a sheet ofmaterial resting upon the pivoted die member and the actuator intoengagement with the abutment and. thereafter impart a rocking movementto the pivoted die member against the tension of said spring, wherebysaid die members will co-operate with each other to bend the sheetmaterial and form an under-cut portion thereon.

4L. An apparatus of the character described having, in combination, aframe, a die member pivotally mounted upon said frame, yielding means tonormally hold said pivoted die member in a raised position, another di-emember slidably mounted upon the frame, means to move the slidable diemember into engagement with sheet material resting upon the pivoted diemember and thereafter impart a rocking movement to the latter againstthe action of said spring, whereby said die members will co-operate witheach other to bend the sheet material to form an under-cut portionthereof, supports projecting laterally from the pivoted die member, anda positioning member for the sheet material adjustably mounted upon saidsupports.

In testimony whereof I have hereunto set my hand.

ARTHUR N. MERRYMAN.

